Hi ,
I think for your first issue you need to look at standard report of sales statistics in BIW.
For the second issue you need to create an Z-transaction to query DFKKOP , with Posting date , Main sub , clearing reason ="01" , XRAGL="blank".
Note - I believe the transactions in question are real (accrual) in nature , so income/revenue is accounted for when sale occurs , not when they are paid (cash payment is received ) , for cash basis transaction you need to post statistical debit , so they hit G/L when payment is received ,so ideally for your sub -transaction you have already recognized revenue/income , regardless of when the payment comes in .